Improvement in locking-knob latches



@Hitch gisten gstmt @fnf CARL HE RRMAN EFFLER, .O Fv NEWT YORK, N. Y.

i Letters Patent No. '71,72Ldatecl December 3, 1867.

IMPROVEMENT IN Leesttte-KNOB LATCHES.

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TO ALL -WHOM IT MAY CONCERN: y n

Be it known that I, Camz. HnnnMAN Emrnnn, vof the city of New York, 209,Bowery, in the county and State of New York, have invented a new anduseful Improvement in Locks; and do hereby declare that the following isa full, clear, andV exact description oi' this invention, which willenable those skilled in the art to make and use the same, referencebcinghad to the accompanying' drawing, forming part of thisspecification, in which drawiug- Figure l represents a horizontalsection of this invention when applied to a door.

Figure 2 is a face view of the locking-mechanism in the door-knob whenthe knob in gear with thelatch.

Figure 3 is a similar view of the same when the knob is out of gear withthe latch.

Figure 4 is a detached face view of the slotted disk for settingthelocking-mechanism in the knob.

Figure 5 is a detached face view of the washer under the door-knob.

` Similar letters indicate corresponding parts.

This invention relates to an improvement in locks of that class whichare generally used on the front doorsl of dwelling-houses, and in-whichthe latch is operated by two knobs, one on the outside and 'the other onthe inside of the door, theoutside knob being constructed in such amanner that it can be thrown in or out of gear with the latch.

My invention consists, first, in the arrangement oi' an `adjustablescrew in the end of the spindle, in such a manner that, by said screw,the length of the spindle and the position of the knob can be regulatedto suit the thickness of the door; second, in enclosing in the knob themechanism which serves to throw said knob in and outof gear with thelatch; third, in the arrangement of a nut on the spindle, in combinationwith a movable stump and tumblers, in such a manner that, when thetumblers are set and the stump made to drop into the I notches thereof,the knob is thrown. in gear' with the latch, and the doo-r can he openedfrom the outside, but if the stump is withdrawn the knob turns freely onthe spindle without having any effect on the latch; fourth, in thearrangement of a safety-stop, in combination with the knob and washerwhich form the socket for said knob,

and with the tuinblers contained in the knob, in such a manner that,when said tumblers andthe knob are brought i in the required position,the stop can be made to lock the outer knob, and prevent it from beingturned, while the inner knob continues to act on the latch; fifth, inthe arrangement of a disk with cam-slots, in combination with themovable stump with the stop and tumblers, in such a manner that, byturning said disk, the stop and stump can be thrown simultaneously outof or in gear wiihthe tumblers, provided sad-tumblers have been broughtin the required position; sixth, in the arrangement of an abutmentbetween the key-holc and safetystop, in such a manner that said stopcannot be reached and it; position disturbed by an instrument introducedthrough the key-hole. y

A represents `a case, made of cast iron, or any other suitable materialcapable of forming the guide and protection of the latch B, and of theordinary locking-mechanism, if such is to be applied. The latch Bisoperated by means'ot` the spindle C, whichextends through the door towhich the lock is attached. To the' inner end of this spindle is securedthe knob D, and to its outer end the knob E, and, in order to adjust thespindle to suit the thickness of the"doorit is provided with a screw, a,the head of which may be square or` round, said screw being secured inthe spindle in the direction of its axis. Through the head of-the screwa, a

hole is bored, which is tapped to receive the set-screw 11,. By thesemeans the length of the spindle C or the` distancebetween thc two.knobs, D E, can be regulated with the greatest niccty, so that, inpulling one ofthe knobs, the spindle will have no longitudinal motion,while said knobs will not interfere with the revolving motionv of thespindle.

The outer end of the spindle C extends into the knob E, which isprovided with amechanism, by means of which it can be thrown in or outof gear with said spindle and with the latch. This mechanism consistsprineipallyl of a nut, c, which is provided with one or moreprojections, and which is secured-,on the spindle C, so that it cannotrevolve independent of the same. This nut acts on a movable stump, d,the position of which'is governed by a cam-slot, c, in the' disk f, andby tumblers g, which turn freely on the outer end of the spindle. Ifthese tumblers are adjusted tothe position shown in iig. 2, all theirnotches, L, register, and the stump d is permitted to enter and toapproach the centre of the spindle C, close enough to allow it to comein contact with the lprojection or projections of the nut c, in whateverdirection the knob may be revolved;

The position of the tumblers g is regulated by the key 7c', which iscomposed of a piece of sheet metal, provided with notches at its ends,and which is introduced throu'ghla slit in the circumference of theknob. Said tumblers hang loosely on the outer end of the spindle andthey nrc provided with-notches li to receive the stump, and with notchesj to receive the head of the safety-stop l. This stop swings on a pivot,m, secured in the shank of the knob E, as shown in g. l, so that, byturning it ou its pivot to the position shown in said figure,.the headcan be made to engage with the notches 7' in the tumbler-s, (providedthe tumbler-s are-properly set,) and, by swinging it back in thedirection ofthe arrow marked on it in iig. 1, its head releases thetuinblers, and its tail end catches in a notch, o, inthe washer F, whichis 'situated between the knob E and the door. 'lhis latter` motion ofthe safety-stop, however, can only take place when the knob is broughtin the proper relation to the washer, said relation being indicatedeither by centre-points or by other suitable marks. The washer F isfirmly secured to the door, and, if the safety-stop'is nia'de to dropinto the notch o, the knob E is iirmly retained in position andprevented from being turned, whatever .the position of the stump oZmaybe. In 'this position the door cannot-beopened from the outside,until,'.by introducing the key, the tumblers are brought in such aposition that their notches L and j will admit'the stump d and the -headof the safety-stop Z. After the tninblers` have been thus adjusted, thestump and stop are forced into the notches ofthe tumblers bythe actionof a disk, f, (see iig. 4,) which is provided with cam-slots e c andwith a button, 1', and which revolves in the hollow body of the knob,its motionbeing limited by the segmental recess s,'i,n which the buttonr moves. If this button occupies the position shown in fig. 2, thestumpd has entered the notch h, and the tail end ofthe safety-stop hasleft the notch o in the'washer, and the knob E is thrown in gear .withthe spindle and latch by the action of the nut c on the stump d, If thcmechanism is in this position, and the knob is turned, -the tai'l end ofthe stop o moves in the `annularlreccss t in the washer F. (See iig. 5.)If the k-nob is thrown out of gear with the latch and locked bythesafety-stop, the door cannot opened fromlthe outside, while the innerknob remains in gear with and operates .on the latch asusual'.

`'lhat portion of .the spindle C next to the outer surface of the dooris made round, so that if the washer F shculd'be forced off from thedoor, said spindle cannot be readily grasped by a wrench or otherinstrument with suicient tenacity to throw'the latch back and to openthe door. The safety-stop o is also protected by an abut ment, u, whichprevents its being reached and thrownout of position by an instrumentintroduced through the key-hole. A

By this arrangement a latch is obtained which cannot be picked, andwhich can be readily changed from one door to another. I y

What I claim as new, and desire to'securc by Letters Patent, is

1. The arrangement of an adjusting-screw, a, provided with a transverseholo to receirc the setiscrew b, in combination with the spindle C andknobs D E, constructed and operating substantially as and for thepurpose sct forth. y

2. Enclosing in the knob E the mechanism which servesto throw saidknobin and out o f gear with the latch, substantially as and for thepurpose set forth. l

3. The nut c. on the spindle C, in combination-with thc'movablc stumpd", tumblersg, knob E, and lntch B, constructed and operatingsubstantially as and for the purpose set forth.A 7

4. The safety-stop o, in combination with the knob E, washer F, andlatch B, constructed and operating substantially as and for the purposedescribed.

5. The disk'j` provided with cam-slots ee, in 'combination with themovable stump'd, safety-stop o, and tumblersg, constructed and operatingsubstantially as and for the'purpose 'set forth.

6. The abutment u, in combination with the key-hole and with thosafety-stop o, constructed and operating substantially as and for thepurpose described.

CARL HERRMAN EIFFLER.

Witnesses:

W. HAUFF, l .GUsrAv BERG.

